Dental implant-carrier assembly

ABSTRACT

A dental implant-carrier assembly is provided, which is a set of elements formed by a dental implant plus a series of removable carrier elements that allow to simplify the procedure of introducing and installing the dental implant in its final location. The dental implant-carrier assembly includes an improved implant design for hard bones, that comprises new cutting sections and threaded taper designs. The carrier elements include an O-ring seal that improves the connection between elements, as well as new hexagonal protruding elements that act as a reference when installing the implant.

FIELD OF THE INVENTION

The invention refers to a dental implant-carrier assembly, which is aset of elements formed by a dental implant plus a series of removablecarrier elements. The dental implant that is used is of the typedescribed in reference WO-A-99/18881.

BACKGROUND OF THE INVENTION

With respect to the implant described in WO-A-99/18881, it has beenobserved that certain features could be improved to increase its initialstability, improve the efficiency of its apical end, and to provide arange of implants that can be used not only for standard applicationsbut also to replace any dental piece.

Carriers used with the mentioned implants; to assist in theirinstallation, have also proved to present several disadvantages.

These carriers consist of three basic parts: a connector, a transportingshaft, and an implant mount connector. The connector is hollow and isfastened to an hexagonal end of the implant. The transporting shaft is ascrew that passes through the connector and threads into the internalaxial cavity of the implant, keeping the connector in place on theimplant. The transporting shaft projects out of the connector forming anabutment to which the implant mount connector is attached.

Existing carriers provide no means of keeping the connection between thetransporting shaft and the implant mount connector in place, thus makingit difficult to move the implant-carrier assembly without thetransporting shaft and implant mount connector falling apart.

In other cases, the connection between the transporting shaft and theimplant mount connector is reinforced by mechanical means, which solvesthe problem mentioned before regarding implant-carrier assemblytransportation. The disadvantage of this, however, is that when theimplant is correctly installed and the carrier elements must then beremoved, it is difficult to extract the implant mount connector, withthe risk that if the implant mount connector is then forced the implantmay be moved out of position or the initial stability lost.

SUMMARY OF THE INVENTION

It is an object of this invention to provide a dental implant-carrierassembly that manages to:

-   -   increase initial implant stability    -   increase implant thread capability    -   comprise a variety of implant sizes so that the implants can be        adjusted to any dental piece    -   facilitate implant transportation and correct positioning    -   allow that the carrier acts as a reference during implant        installation, so that when several implants are installed, all        implants can be positioned with the hexagon in the same        position, thus making the orthodontist's work easier.

To achieve these objectives, the implant that showed pairs of cuttingedges on its apical is modified by slightly inclining each straightcutting edge. Thus, while in the case of WO-A-99/18881 the straightcutting edge operated in a radial direction in relation to the center ofthe implant, in the present invention each straight cutting edgemaintains its position at its end and leans back at a slight angle, sothat it is the aforementioned end that cuts into in the bone initiallyand advances gradually to make the threading softer and less aggressive.The lean-back angle of these straight cutting edges ranges from 0° to20°.

In the upper part of the implant, the area connecting the implant headto the threaded section of the implant has a taper of between 50 and65°. Tests have been carried out that show that this degree of taperingin this area creates greater initial stability once the implant has beenthreaded in, without causing a significant increase in the distributionof stresses and even decreasing them.

As stated above, the general sizes of the implant are also modified,with the two above-mentioned features being retained as standardfeatures thus creating a standard implant or implant type. Another twoimplant types are also defined, to be applied to lower incisors and tomolars respectively, as well as another one that has been speciallydesigned for hard and very hard bones, which we shall look at in moredetail later.

The upper head in the standard implant has a diameter of 4.1 mm, and theupper hexagon measures 2.7 mm between faces and is 0.7 mm high, whilethe threaded section can have a diameter of 3.3, 3.75 and 4 mm.

The diameter of the incisor implant head is 3.6 mm, and the hexagonmeasures between 2.4 and 2.6 mm between faces and is 1 mm high. Thediameter of the threaded section is 3.3 mm.

The diameter of the molar implant head is 5.5 nun, and the hexagonmeasures between 2.7 and 3.5 mm between faces and is between 0.7 and 1.2mm high. The threaded section can have a diameter of 4, 4.5, 5, 5.5 and6 mm.

It should also be pointed out that the performance of these implants canbe improved, particularly when they are used to carry out work onpatients with hard or very hard bones, by providing them with a moreaggressive and therefore more effective cut, allowing excess bone fromthe operation to be removed more easily.

According to this invention, the implant is provided with cutting areasthat begin right on the flat part of the apical end, and extendoutwardly for a certain distance in the radial direction.

The aforementioned cutting areas end some distance before the positioncorresponding to the base of the tapered threaded section, thus leavingenough space in-between to allow the excess bone to move out normallytowards the removal area behind each cutting area, which, in existingimplants, is in the form of a tapered convex shape pointing outwards.

Standard sizes have been discovered that will make the aforementionedimplant design perform better, all of which are based on theaforementioned features. These sizes refer to the length of the implant,the angles of the tapered threaded sections and the removal areas aswell as the length of the implant's tapered threaded sections.

These sizes are adjusted according to the following measurements:

L C α β 8.5 2.9 9°   4.2° 10 2.9 9°   4.2° 11.5 4.6 5.22° 3.3° 13 4.65.22° 3.3° 15 4.6 5.22° 3.3° 18 4.6 5.22° 3.3° 20 4.6 5.22° 3.3° L.length of the implant in millimeters. C. Length of the tapered threadedsection in millimeters. α Angle of the tapered threaded section. β Angleof the removal area.

The carrier defined by the present invention has two specific features.One of these features is a hexagonal abutment on the outer end of theconnector, the position of which matches the position of the hexagonalcavity with which the connector is provided to receive the hexagonal endof the implant.

Thus, when the carrier transports and places the implant in the desiredlocation, the position of the connector's hexagonal abutment will matchthe position of the hexagonal end of the implant, and therefore act as areference during implant installation. When installing several implants,the aid of this reference enables the implants to be situated in anidentical position, leading to many prosthodontic advantages.

As a second feature, the projecting part of the transporting shaft,which is embraced by the implant mount connector, is provided with anannular neck into which an O-ring seal made of suitable material isfitted. When the implant mount connector embraces the transportingshaft, the O-ring seal keeps the implant mount connector correctlyfastened to the transporting shaft, and therefore also to the connectorand the implant. Furthermore, the implant mount connector can be removedfrom the transporting shaft when required without any difficultywhatsoever, without the position and the stability of the implant beingaffected in any way.

The threaded section of the implant can incorporate a double thread toenable it to be screwed more quickly into the patient's bone.

The speed with which the implant is screwed in will, in any case, dependon the circumstances. The size of the carrier will be adjusted to thesize of the implant. Each implant will thus have a correspondingcarrier, although the features set out in the invention and describedabove will be retained.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other aspects of the preferred embodiment of the invention canbe seen in greater detail in the drawings attached, details of which aregiven below:

FIG. 1 is an elevation view of the implant according to the invention.

FIG. 2 is a lower view of FIG. 1.

FIG. 3 is an upper view of FIG. 1.

FIG. 4 is a mid-section elevation view of the one of the carrier'scomponents: the connector.

FIG. 5 is a view of FIG. 4 from the right.

FIG. 6 is a view of FIG. 5 from the left.

FIG. 7 is an elevation view of another of the carrier's components: thetransporting shaft.

FIG. 8 is a view of FIG. 7 from the left.

FIG. 9 is an elevation view of another of the carrier's components: theimplant mount connector, with a cross-section of the left end.

FIG. 10 is a view of FIG. 9 from the left.

FIG. 11 is an elevation of an implant for hard or very hard bones,according to the invention.

FIG. 12 is a view from above of FIG. 11.

DETAILED DESCRIPTION OF THE DRAWINGS

As can be seen in FIGS. 1, 2 and 3, the implant consists of a threadedsection (1), an apical end (3), and an upper section comprising the head(5) and the hexagonal end (4), to facilitate its insertion andprosthodontic reconstruction. The head (5) is connected to the threadedsection (1) through a tapered section (2), which has a taper of between48 and 65°, and a cylindrical section with a height (a) of 0.5 mm.

In FIG. 2 we can see the line or straight cutting edge (6) of the apicalend. The figure shows that it is separated from the radial position insuch a way that the end that is furthest away projects forward to makethe cut, and does so by rotating in an anti-clockwise directionaccording to the position in FIG. 2.

The fact that this cutting edge (6) is inclined at an angle of between 0and 20° in relation to the radial position and the anti-clockwisedirection of the rotation means that it enters more deeply when itbegins cutting and does so more gradually and smoothly, but also moreeffectively, which is the aim of the invention.

In FIG. 1 we can also see the blind threaded hole (13), which extendsaxially from the hexagonal end (4), with said hole and hexagonal endbeing the features that are typically used to position the transportingshaft, the connector, and the prosthodontic components.

To achieve this, the connector (7) in FIG. 4 is positioned in such a waythat its hexagonal cavity (10) embraces the implant hexagonal end (4),while the transporting shaft (11) in FIG. 7 is introduced through theconnector (7), and its threaded end (12) is screwed into the blindthreaded hole (13) of the implant. When being introduced, the threadedend (12) of the transporting shaft (11) passes through the internalthreaded section (23) of the connector, thus guiding the transportingshaft into place.

In conventional usage of the implant and carrier of the figures, whenthe connector (7) and the transporting shaft (11) are mounted on theimplant, the end (16) of the transporting shaft (11) protrudes outwards.This end (16) is then housed in the interior (20) of the section (19) ofthe implant mount connector (17) of FIG. 9, so that when a suitable toolis used, for example, connected to the end (18), it moves the implantcarrier assembly into the desired position.

By this invention, the connector (7) is provided with the hexagonalparts (8, 9). The position of the faces of these hexagonal parts (8, 9)match the faces of the hexagonal cavity (10) of said connector, andtherefore also match the faces of the hexagonal end (4) of the implant.

The fact that the position of the hexagonal faces of the aforementionedparts coincide means that, irrespective of the condition of theimplant-carrier assembly, there will always be a valid referenceindicating the exact position of the hexagonal end (4) of the implant.

When transporting and placing the dental implant-carrier assembly, thehexagonal base (8) of the connector provides a positional reference.When the implant mount connector (11) is removed, the reference is thenprovided by the hexagonal parts (8, 9) of said connector (7). In otherwords, the position occupied by the hexagonal end (4) of the implantwill always be able to be identified.

In FIG. 7 we can see that the transporting shaft (11) is provided withthe O-ring seal (14), housed in an annular neck between end (16) andabutment (15). When this end (15, 16) is housed in the interior (20) ofthe implant mount connector (17), the O-ring seal (14) presses againstthe inner walls of the interior (20) thus keeping the implant-carrierassembly perfectly in position.

Once the implant-carrier assembly has been moved and positioned asdesired, the implant mount connector (11) is then removed. The pressureexerted by the O-ring seal (14) allows this to be done easily andsmoothly.

These structural modifications enable the dental implant-carrierassembly to provide significantly improved performance, thus meeting theobjectives of the invention.

The flat part (21) and four cutting areas (24) present in the apical endof the implant (27) can be seen in FIG. 11. With existing techniques thelaterals protrude from the surface of the apical end. The flat part (21)and four cutting areas (24) limit the tapered threaded section (22),which on the opposite side, extends up to the edge (26). The implantruns from this apical end to its opposite hexagonal end, where itconnects with the implant manipulating tool (carrier, etc.). The headand the hexagonal end of the implant, which are not numbered, can beseen at this opposite end.

As detailed in FIG. 12, we can see the four cutting areas (24), whichradiate out from the flat part (21) until they reach a circular section(29) at a certain distance from the edge (26). This distance provides agap through which the cut bone is directed to the removal area (28)behind the cutting areas (24).

As can be seen in FIGS. 11 and 12, the tapered threaded section (22)runs from the circular section (29) and vertical wall (25), towards thetapered convex removal area (28).

The angles (α) and (β) in FIG. 11 determine the measurements of thetaper of the tapered threaded section (22) and the removal area (28).

As the implant head has diameters of 4.1 mm or 5.5 mm and the hexagoncan protrude above this head by 0.7 mm or between 0.7 and 1.2 mm, theinvention can evidently be applied to the technique outlined in thereports quoted at the beginning of this document.

1. A dental implant-carrier assembly, designed to facilitate dentalimplant transportation and installation, that comprises: a dentalimplant comprising a threaded section, an apical end having at least onestraight cutting edge, a head, a hexagonal end protruding out of thehead, and a blind threaded cavity; and a carrier comprising a connector,a transporting shaft and an implant mount connector, wherein theconnector is mounted on the hexagonal end, the transporting shaftcomprises a threaded end that passes through the connector and isscrewed into the implant blind threaded hole, and the transporting shaftcomprises a free end that is operated by the implant mount connector,wherein the area connecting the implant head to the threaded section ofthe implant has a taper of between 48 and 65°; the straight cutting edgeof the apical end of the implant is inclined relative to a radialposition and behind the radial position in a direction of movement ofthe cutting edge at an angle of greater than 0° and less than or equalto 20°, wherein the outermost end of the cutting edge is the part thatfirst makes contact with the area to be cut; the connector comprises anabutment comprising a hexagonal abutment situated on a hexagonal base,the sides of the hexagonal abutment and the hexagonal base being in linewith each other and with the faces of the hexagonal end of the implant;the connection between the implant mount connector and the transportingshaft comprises an O-ring seal positioned at the projecting end presentin one of the parts of the connection, the projecting end being housedin a cavity present in another one of the parts of the connection.
 2. Adental implant-carrier assembly, according to claim 1, wherein in itsapplication to incisors, the diameter of the implant head is 3.6 mm, thehexagonal end measures between 2.4 and 2.6 mm between faces and is 1 mmhigh, and the diameter of the threaded section is 3.3 mm.
 3. A dentalimplant-carrier assembly, according to claim 1, wherein in itsapplication to molars, the diameter of the implant head is 5.5 mm, thehexagonal end measures between 2.7 and 3.5 mm between faces and isbetween 0.7 and 1.2 mm high, and the threaded section can have adiameter of 4, 4.5, 5, 5.5 or 6 mm.
 4. A dental implant-carrierassembly, according to claim 1, wherein the dental implant comprisescutting areas that radiate out from a flat part on the apical end, thatcreate respective vertical walls, and that are crowned by circularsections from which the tapered threaded implant begins, the taper ofthe exterior of threaded section is determined by a generator angle (β)of between 9 and 5.21°, in relation to the vertical, while the generatorangle (α) of the taper of the interior of the threaded section is set atbetween 4.2 and 3.3° in relation to the vertical, with these valuesbeing adjusted to total implant lengths ranging from 8.5 to 20 mm and tothe lengths of the tapered threaded section, which range from 2.9 to 4.6mm.
 5. A dental implant-carrier assembly, according to claim 1, whereinthe sizes of the carrier are adjusted according to each implant.
 6. Adental implant-carrier assembly, according to claim 1, wherein astandard implant comprises a head with a diameter of 4.1 mm, a hexagonalend that measures 2.7 mm between faces and is 0.7 mm high, and athreaded section that has a diameter of 3.3, 3.75 or 4 mm.